/Engine/Plugins/MeshPainting/Source/MeshPaintingToolset/Public/TexturePaintToolset.h
Will generate a mask texture, used for texture dilation, and store it in the passed in render target
static bool GenerateSeamMask ( [UMeshComponent](API\Runtime\Engine\Components\UMeshComponent) * MeshComponent, int32 UVSet, [UTextureRenderTarget2D](API\Runtime\Engine\Engine\UTextureRenderTarget2D) * SeamRenderTexture, [UTexture2D](API\Runtime\Engine\Engine\UTexture2D) * Texture, [UTextureRenderTarget2D](API\Runtime\Engine\Engine\UTextureRenderTarget2D) * RenderTargetTexture )